ERAS · Erasca, Inc.

This disclosure represents a high-materiality clinical milestone for Erasca, as it presents the first human evidence of robust, dose-dependent antitumor activity for ERAS-0015 — a pan-RAS molecular glue targeting historically undruggable RAS mutants. The 62% uORR in second-line or greater KRAS G12X NSCLC and 40% uORR in second-line KRAS G12X PDAC significantly exceed comparator benchmarks from non-head-to-head trials (RMC-6236 and others), though the filing explicitly cautions that cross-study comparisons are inherently limited. Critically, the pharmacodynamic data — 100% of evaluable patients achieving ≥75% ctDNA reduction — provides mechanistic validation of RAS pathway shutdown, reinforcing the company’s core therapeutic hypothesis. Safety was generally favorable with no DLTs, supporting advancement into expansion cohorts; however, the single Grade 5 pneumonitis event warrants close monitoring in broader populations. The selection of 24 mg and 32 mg QD as monotherapy RDEs sets the stage for imminent data readouts from expansion cohorts in the first half of 2027. Importantly, the filing notes that these are preliminary, unconfirmed results subject to change with additional follow-up and larger datasets — a key risk highlighted in the forward-looking statements section. For investors, this data strengthens the clinical rationale for ERAS-0015’s potential best-in-class positioning and supports near-term value inflection points tied to upcoming expansion cohort updates.